I have also had great results with a homeopathic remedy called Argentum Nitricum (for anxiety, fear & panic attacks).
I have had great results using Argentum Nitricum & Rescue Remedy at the same time when I have felt my heart starting to race.
I have also used the essential oil, Frankincense, and I just hold the bottle under my nose & smell it in. It has a calming effect on the emotions.